Update CrateDB in testing layer to 4.2.3.

Author: kovrus

.github/workflows/main.yml

@@ -31,11 +31,6 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
 
-      - name: Set up Java
-        uses: actions/setup-java@v1
-        with:
-          java-version: 11
-
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
@@ -58,4 +53,4 @@ jobs:
       - name: Test
         run: |
           bin/flake8
-          JAVA_HOME=$JAVA_HOME_12_X64 bin/coverage run bin/test -vv1
+          bin/coverage run bin/test -vv1

versions.cfg

@@ -1,5 +1,5 @@
 [versions]
-crate_server = 4.0.2
+crate_server = 4.2.3
 
 flake8 = 3.7.9
 mccabe = 0.6.1